- Italy--Vernio1
- Italy--Vicopisano1
- Iṣfahānī, Maḥmūd ibn ʻAbd al-Raḥmān, 1275 or 1276-1348 or 1349. Tashyīd al-Qawāʻid1
- Jacopo, Bernardo di1
- Jacopo, Giovanni di1
- Jaghmīnī, Maḥmūd ibn Muḥammad, -1221?1
- Jean, de Verdun1
- Jewish astronomy1
- Jewish ethics1
- Jewish ethics in literature1
- Jewish law1
- Jews--Legal status, laws, etc.1
- Jews--Persecutions1
- Jighmīnī, Maḥmūd ibn Muḥammad, -1221? Mulakhkhaṣ fī al-hayʼah1
- Jiří, z Poděbrad, King of Bohemia, 1420-14711
- Joannes de Caligariis1
- John, of Daylam1
- Juan II, King of Castile and Leon, 1405-14541
- Judaism--Customs and practices1
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